Cryptopals solutions

Solutions to the Cryptopals crypto challenges in C++.

The repo is organized as:

• CCrypto/ — a small shared library (libCCrypto) with the crypto primitives and utilities used by the challenges (hex/base64 conversion, XOR, English-text scoring, hamming distance, PKCS#7 padding, ...).
• Challenges/setN/ — one .cpp/.h pair per challenge (e.g. S01C06 = Set 1, Challenge 6), plus a shared main.cpp that dispatches to the right challenge based on the SET/CHALLENGE build variables.
• assets/ — sample data files used by the challenges (English text sample, ciphertexts, ...).

Progress

Set	Challenges done
1	1–8
2	1

Requirements

• g++ with C++23 support
• make
• libssl-dev (OpenSSL headers, the library links against libcrypto)

Optional

• bear — to (re)generate compile_commands.json for clangd/LSP support
• Docker + Docker Compose — see DEV.md for a containerized dev environment (neovim + tmux + Claude Code CLI, no local toolchain required)

Build

From the repo root:

make

This builds CCrypto and, by default, Set 1 / Challenge 1 in debug mode.

Pick a specific challenge and build type with variables:

make SET=1 CHALLENGE=6              # debug build (default)
make release SET=2 CHALLENGE=1      # release build

The resulting binary is placed at:

bin/debug/cryptopalsS<SET>C<CHALLENGE>     # BUILD=debug (default)
bin/release/cryptopalsS<SET>C<CHALLENGE>   # BUILD=release

Run it directly, e.g.:

make SET=1 CHALLENGE=6 && ./bin/debug/cryptopalsS1C6

Other Makefile targets

make list              # list available challenge sets
make clean             # remove build artifacts (challenges + CCrypto)
make clean-all         # clean plus remove build/bin directories
make compile_commands  # regenerate compile_commands.json with bear
make help              # show all targets and variables

Development environment

See DEV.md for how to work inside the provided Docker dev container (neovim, tmux, and Claude Code preconfigured, no need to install a local toolchain).